import React, { Component } from "react";
// 引入action
import {
  createIncrementAction,
  createDecrementAction,
  createIncrementAsyncAction,
} from "../../redux/count_action";
// 引入connect同于连接UI组件与redux
import { connect } from "react-redux";

class Count extends Component {
  state = { carName: "奔驰c63" };

  // 加法
  increment = () => {
    const { value } = this.selectNumber;
    this.props.increment(value * 1);
  };
  //减法
  decrement = () => {
    const { value } = this.selectNumber;
    this.props.decrement(value * 1);
  };
  //奇数再加
  incrementIfOdd = () => {
    const { value } = this.selectNumber;
    if (this.props.count % 2 !== 0) {
      this.props.increment(value * 1);
    }
  };
  //异步加
  incrementAsync = () => {
    const { value } = this.selectNumber;
    this.props.incrementAsync(value * 1, 500);
  };

  render() {
    // console.log(this.props);
    return (
      <div>
        <h1>当前求和为：{this.props.count}</h1>
        <select ref={(c) => (this.selectNumber = c)}>
          <option value="1">1</option>
          <option value="2">2</option>
          <option value="3">3</option>
        </select>
        &nbsp;
        <button onClick={this.increment}>+</button>&nbsp;
        <button onClick={this.decrement}>-</button>&nbsp;
        <button onClick={this.incrementIfOdd}>当前求和为奇数再加</button>&nbsp;
        <button onClick={this.incrementAsync}>异步加</button>&nbsp;
      </div>
    );
  }
}

/* 
  1.mapStateToProps函数返回的是一个对象
  2.返回的对象中的key作为状态传递给了UI组件props的key，value就作为传递给UI组件props的value
  3.mapStateToProps用于传递状态状态
*/
const mapStateToProps = (state) => ({ count: state });

/*
  1.mapDispatchToProps函数返回的是一个对象
  2.返回的对象中的key作为状态传递给了UI组件props的key，value就作为传递给UI组件props的value
  3.mapDispatchToProps用于操作状态的方法
*/
// mapDispatchToProps一般写法，传入一个函数
// const mapDispatchToProps = (dispatch) => {
//   return {
//     increment: (number) => {
//       // 通知redux执行加法
//       dispatch(createIncrementAction(number));
//     },
//     decrement: (number) => dispatch(createDecrementAction(number)),
//     incrementAsync: (number, time) =>
//       dispatch(createIncrementAsyncAction(number, time)),
//   };
// };
// 创建并暴露一个Count的容器组件
export default connect(
  mapStateToProps,
  // mapDispatchToProps一般写法，传入一个函数
  // mapDispatchToProps的简写传入一个对象,底层会自动分发
  {
    increment: createIncrementAction,
    decrement: createDecrementAction,
    incrementAsync: createIncrementAsyncAction,
  }
)(Count);
